An air bag module typically comprises an air bag and an air bag inflator. Both the air bag and the air bag inflator are stored within a housing until deployment of the air bag. When the air bag deploys, the air bag inflator fills the air bag with inflation gas, causing the air bag to expand through a mouth of the housing. To ensure proper deployment of the air bag, the air bag is typically secured to the air bag housing by a retaining frame, which is inserted into the housing and snapped into place. However, this retaining frame adds significant cost to the air bag module.
Manufacturers have sought to eliminate the retaining frame. One proposed design attaches the air bag to hooks on the outside of the air bag housing. However, such a design allows excessive amounts of inflation gas to leak between the air bag and the exterior surface of the air bag housing. As a consequence, the air bag might under-inflate.
A need therefore exists for an improved air bag module that eliminates the retaining frame without the drawback of existing designs.